Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/sound/oss/dmasound/Kconfig b/sound/oss/dmasound/Kconfig
index f456574..1a33398 100644
--- a/sound/oss/dmasound/Kconfig
+++ b/sound/oss/dmasound/Kconfig
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
 config DMASOUND_ATARI
 	tristate "Atari DMA sound support"
 	depends on ATARI && SOUND
@@ -10,7 +11,7 @@
 	  This driver is also available as a module ( = code which can be
 	  inserted in and removed from the running kernel whenever you
 	  want). If you want to compile it as a module, say M here and read
-	  <file:Documentation/kbuild/modules.txt>.
+	  <file:Documentation/kbuild/modules.rst>.
 
 config DMASOUND_PAULA
 	tristate "Amiga DMA sound support"
@@ -24,7 +25,7 @@
 	  This driver is also available as a module ( = code which can be
 	  inserted in and removed from the running kernel whenever you
 	  want). If you want to compile it as a module, say M here and read
-	  <file:Documentation/kbuild/modules.txt>.
+	  <file:Documentation/kbuild/modules.rst>.
 
 config DMASOUND_Q40
 	tristate "Q40 sound support"
@@ -38,7 +39,7 @@
 	  This driver is also available as a module ( = code which can be
 	  inserted in and removed from the running kernel whenever you
 	  want). If you want to compile it as a module, say M here and read
-	  <file:Documentation/kbuild/modules.txt>.
+	  <file:Documentation/kbuild/modules.rst>.
 
 config DMASOUND
 	tristate
diff --git a/sound/oss/dmasound/Makefile b/sound/oss/dmasound/Makefile
index 3c15316..de8ae83 100644
--- a/sound/oss/dmasound/Makefile
+++ b/sound/oss/dmasound/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
 #
 # Makefile for the DMA sound driver
 #
diff --git a/sound/oss/dmasound/dmasound_atari.c b/sound/oss/dmasound/dmasound_atari.c
index a1a2979..823ccfa 100644
--- a/sound/oss/dmasound/dmasound_atari.c
+++ b/sound/oss/dmasound/dmasound_atari.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  *  linux/sound/oss/dmasound/dmasound_atari.c
  *
@@ -1431,25 +1432,25 @@
 {
 	int data;
 	switch (cmd) {
-	    case SOUND_MIXER_READ_RECMASK:
+	case SOUND_MIXER_READ_RECMASK:
 		return IOCTL_OUT(arg, SOUND_MASK_MIC);
-	    case SOUND_MIXER_READ_DEVMASK:
+	case SOUND_MIXER_READ_DEVMASK:
 		return IOCTL_OUT(arg, SOUND_MASK_VOLUME | SOUND_MASK_MIC | SOUND_MASK_SPEAKER);
-	    case SOUND_MIXER_READ_STEREODEVS:
+	case SOUND_MIXER_READ_STEREODEVS:
 		return IOCTL_OUT(arg, SOUND_MASK_VOLUME | SOUND_MASK_MIC);
-	    case SOUND_MIXER_READ_VOLUME:
+	case SOUND_MIXER_READ_VOLUME:
 		return IOCTL_OUT(arg,
 			VOLUME_ATT_TO_VOXWARE(dmasound.volume_left) |
 			VOLUME_ATT_TO_VOXWARE(dmasound.volume_right) << 8);
-	    case SOUND_MIXER_READ_CAPS:
+	case SOUND_MIXER_READ_CAPS:
 		return IOCTL_OUT(arg, SOUND_CAP_EXCL_INPUT);
-	    case SOUND_MIXER_WRITE_MIC:
+	case SOUND_MIXER_WRITE_MIC:
 		IOCTL_IN(arg, data);
 		tt_dmasnd.input_gain =
 			RECLEVEL_VOXWARE_TO_GAIN(data & 0xff) << 4 |
 			RECLEVEL_VOXWARE_TO_GAIN(data >> 8 & 0xff);
-		/* fall thru, return set value */
-	    case SOUND_MIXER_READ_MIC:
+		/* fall through - return set value */
+	case SOUND_MIXER_READ_MIC:
 		return IOCTL_OUT(arg,
 			RECLEVEL_GAIN_TO_VOXWARE(tt_dmasnd.input_gain >> 4 & 0xf) |
 			RECLEVEL_GAIN_TO_VOXWARE(tt_dmasnd.input_gain & 0xf) << 8);
diff --git a/sound/oss/dmasound/dmasound_paula.c b/sound/oss/dmasound/dmasound_paula.c
index 81eb82c..23cf828 100644
--- a/sound/oss/dmasound/dmasound_paula.c
+++ b/sound/oss/dmasound/dmasound_paula.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  *  linux/sound/oss/dmasound/dmasound_paula.c
  *
diff --git a/sound/oss/dmasound/dmasound_q40.c b/sound/oss/dmasound/dmasound_q40.c
index be4fe15..e25a78d 100644
--- a/sound/oss/dmasound/dmasound_q40.c
+++ b/sound/oss/dmasound/dmasound_q40.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  *  linux/sound/oss/dmasound/dmasound_q40.c
  *